Living with flooding is part of life in the Brisbane River catchment, and as a community we need to be informed, ready and resilient.
The 2011 Brisbane flood is still fresh in the minds of many as one of the more recent devastating floods in South East Queensland.
The 2011 Floods Commission of Inquiry recommended that a comprehensive flood study of the Brisbane River catchment be carried out to identify areas at risk of flooding during extreme rainfall.
The Queensland Government is leading a key component of the Brisbane River Catchment Flood Studies. The studies are designed to provide us with a better understanding of and ability for long term planning of the Brisbane River catchment and its floodplain.
The study is one of Australia’s most comprehensive flood studies.
Brisbane River Catchment Floodplain Studies
Wivenhoe and Somerset Dams Optimisation Study
As the first output from the Brisbane River catchment studies, the Queensland Government completed the Wivenhoe and Somerset Dams Optimisation Study in 2014. This study presented options for improving the use of existing dam infrastructure to deliver better flood mitigation outcomes ahead of the 2014-15 summer wet season, without putting future water supplies at risk.
Under the adopted operational strategy, more flood water will be released earlier from Wivenhoe Dam to increase water storage space in case a large flood eventuates. While this may result in some crossings, like Colleges Crossing in Ipswich, being closed more regularly, it will mean that fewer buildings (around 500 to 1500) may be affected in Brisbane and Ipswich if a flood of a similar magnitude to 2011 was to occur.
The Brisbane River Catchment Flood study
The flood study is well underway and will deliver comprehensive models of the river catchment. The study builds on the existing work undertaken by the Brisbane River catchment councils, Seqwater and the State Government.
This study involves a hydrologic assessment (now complete) and a hydraulic assessment (currently underway). The flood study is expected to be completed early 2017.
Together these assessments aim to deliver consistent, up-to-date technical flood data for local governments and other users across the Brisbane River catchment to help better plan for and minimise the impacts of future floods.
Brisbane River Catchment Floodplain Management Study
The Brisbane River Catchment Floodplain Management Study (BRCFMS) will identify floodplain risks and assess various flood mitigation and management measures to increase the community's resilience to floods in the Brisbane River catchment (including the Bremer River, Lockyer Creek and smaller tributaries).
The recommendations from the BRCFMS will form the basis of catchment-wide and local area specific floodplain management plans to be used by the state and councils. This will enhance government and community ability to better respond to rainfall events. The study is due for completion in late 2017.
Catchment-wide and local area specific floodplain management plans will be used by state government and the four catchment area councils to prioritise a range of infrastructure projects and guide land use planning to better manage residual flood risks. The plans will assist councils in updating sub-catchment plans to ensure their communities are informed, ready and resilient.
The final management plans will be important tools to help protect Queenslanders from future flood events so it is important that they are technically robust and achieve best practice outcomes for many years to come. The plans will take some time to finalise and are likely to be released in 2018.
In the meantime, state and local governments will use an interim disaster management modelling tool that was developed in 2013 as part of the flood studies in the event of flooding rain.
To obtain further information on the Brisbane River Catchment Study, including purpose, methodology and timing, please read our Understanding the Brisbane River Catchment Flood Study ( 369 KB) fact sheet. For more details about the hydrologic and hydraulic studies, please read our Brisbane River Catchment Floodplain Study ( 616 KB) brochure.